the Avengers Shadow
by superatheart1990
Summary: While on a "team building mission" the avengers uncover a seemingly dead girl in a tank. haunted by her past will she be the help they desperatly need in the upcoming battle with Thanos, or will she provide her own problems that could ruin the team for good?
1. Chapter 1

**this is my first time writing any fan fiction and it will get better i promise. i may need some help along the way so any positive review would be helpful and suggestions will be noted :)**

_The snow was cold against the skin of her arms, reminding her that her cloak needed readjusting to cover them. She looked up toward the northern border of her village. Something had woken her so leaving the comfort of her bed she stepped out of the homestead into the cold morning air to investigate. The wind whipped her long black hair in front of her eyes, groaning she pulled her hand out of her cloak and pushed it back behind her ear. Upon doing so she held back a scream, smoke rose from the woodland, blackening the morning sky. From the tree line shadowing figures moved about. Gathering herself she called out to her village running back inside her homestead waking the chief, her father..._ I think you better take a look at this..._what was that? The blood covers the snow screams fill the air..._take it back to the Hellicarrier..._I see my mother lying dead, my father standing beside her..._Vitals are bad are you sure she'll pull through..._His body is cut down by a barbarian on horseback throwing it to my mother's side..._beep, beep, beep_...that noise, what is it? The man on the horse is moving forward towards me, axe raised. I can't out run him but I turn and try..._beep, beep, beep, beep_...and again, it's getting louder. The pain is almost numbing, I scream as I am lifted from the ground by the axe in my back and thrown to the ground. My vision blurs before going black..._Its Remarkable. Beep, beep, beep_... I wake, am I dead? No. The ground is stained with blood, the air filled with smoke and my village lay ransacked and destroyed. Everyone is dead and gone, except me, I am alone. I sit and cry, I know what that sound is..._

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"Nothing like a mission to a remote corner of Russia to strengthen the team, right cap?" Stark looked back at his team mate with a smile, although he knew the captain wouldn't pick up on the sarcasm.

"I would hardly call it 'remote'" replied Rogers in a matter-of-fact tone, "That is why Fury sent us. This military base we're heading to is supposedly trying to create stronger, more efficient soldiers for war."

"So the real reason is to stop the Russians from making more of you 'cause that would mean you're less special," Tony retorted, his grin widening.

"Enough," groaned Natasha, she was fed up of having to co-pilot with Clint she didn't want to hear Starks jibes as well, "besides we're 3 minutes out from the drop zone, after that Clint and I will land the jet and join you. From that point on we have exactly 15mins to secure the base before the Hellicarrier comes in for landing, understood?"

"got it", Captain America stood up from his seat, pulling plans of the base and putting them in-between Iron main and himself, "Stark once we get past the security turrets and the fences if you head to the main research facility located here," he pause pointing at the map, "while I head to the main guard building and cover you," Stark nodded, "then when Black widow and Hawkeye, take out any stragglers and other threats, agreed?"

"No problem Captain," Stark replied covering his face with his helmet.

"Agreed," nodded a stern faced Hawkeye.

"Agreed," spoke Black widow before adding, "don't forget the research lab is out main priority. We need it undamaged for Banner when he gets here, and be careful they may already have succeeded in making super soldiers."

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	2. Chapter 2

Luckily for them the base hadn't managed to create a super soldier on Captain America's level but the soldiers there were strong enough to cause trouble. In fact by the time they had made it to the science lab in the middle of the base they were almost running out of time.

Stark lead the way crashing the doors through with Captain America closely behind with both Hawkeye and Black widow bringing up the rear, their guns pointing in different directions ready to shoot. The room was filled with various tanks letting off blue and green light, the only light that filled the room. Inside the tanks were men, tubes and breathing apparatus surrounding them. The rest of the room had every type of lab equipment imaginable whilst huddled in the furthest corner of the room were ill looking men and women in lab coats guarded by two soldiers who quickly turned, pointing their guns towards the Avengers. Captain America quickly let go of his shield, throwing it at the guards and knocking them out, and then caught it again. The cornered scientists let out a collective sigh but still were unsure of their predicament.

"Area is secure Director," Natasha informed Fury through her earpiece, "awaiting your arrival."

"Good," Fury responded from the Hellicarrier, "we are coming in now, sit tight and see if there is any usable Intel in the lab. Don't let anyone leave the base and keep those alive secure."

"On it," she nodded taking her hand away from the earpiece.

"right," breathed Steve, "Ironman you know about this technology stuff..."

"understatement," interjected Tony, "but continue"

Captain America frowned but continued, "search the lab computer systems and paper work for stuff you and Banner my find useful, Hawkeye and Black Widow do another sweep of the base and secure."

Each of them nodded and went about following the orders.

Steve made his way to the scientists but stopped as his eye caught a glimpse of something hidden in the corner. He changed his course and made his way to the tank, it was partially covered by a sheet, but it was still clear what was inside. Unlike the other tanks that had muscular men inside and were clean this was covered in a thick layer of dust and held what seem to be the remains of a child or small woman. After collecting himself he called out.

"hey Stark!" Steve called, "I think you better take a look at this."

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Everyone was staring at the tank by the time Fury entered the lab. The girl inside looked frail, she was missing an arm on her left side, part of her right leg and her right arm was severely damaged. The most of her body was burned and scarred while the rest of her was unusual pale. Her face was also too burnt to be recognisable and she had very little hair. But she looked peaceful, floating in the tank with no breathing apparatus and her mouth slightly opened.

"A failed experiment?" Tony suggested, tilting his head, "they tried to see if she was fire proof?"

"Either way, I think it's safe to say she didn't make it," pitied Steve.

Fury strode up and stood beside Natasha, "damn it," the others looked at him, "Grab the tank take it back to the Hellicarrier." He turned his coat billowing behind him as he walked away.

"Is there any point?" questioned Stark, "I mean is there anything we could gain from it?"

"Yes, there is," called Fury turning round, "She's one of ours."

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	3. Chapter 3

Bruce rubbed the sides of his nose between the eyes and chugged down a cup of Coffee.

"I'm not that kind of a doctor you know," he sighed reaching for his clipboard, "I mean sure I worked on researching the implications of super soldier serum on different blood type, trying to cultivate and reproduce the previous results, but I mainly work in Gamma."

"I Know Dr. Banner but I don't really need the other type of doctor for her," Fury explained, " i just need someone I trust to keep an eye on her and let me know if there's any change."

"Any change?" Bruce quipped, "look at her, she looks like she's just been hit by an A-Bomb and you've got her hooked up to life support systems? She dead Director!"

"Dr. Banner please calm down, she has come back from worse, just please keep an eye on her," Fury was trying his best to explain to the doctor even though he himself never really understood. He looked down at the small body between them. She had been taken to out of the tank and place in a hospital bed on the Hellicarrier, since then only Fury and Banner had clearance to the room.

"O.K I'll keep an eye on her," Bruce said as calmly as he could," he moved to his desk sitting down and continuing with other work, "I take it I don't need to tell you that her vitals are bad, are you sure she'll pull through?"

"yes."

"Fine but I still want an explanation," Bruce mumbled delving deep into his work.

"You'll get one, tomorrow morning at Stark Tower 11am. By that time I expect a full report and copies made for those attending."

"Seriously, a report as well? Are you making Stark do one?"

"Yes, but I doubt he will," Fury left the room ready to prepare for tomorrow leaving Bruce alone with the 'patient'.

After an hour working in complete silence an annoying beeping filled the air. Bruce groaned angrily before realising what it was. Rushing to the side of the bed he looked at the monitor and the line moving up and down indicating a heartbeat. Gobsmacked he looked down at the body on the bed, checking her pulse for himself and watching her chest move up and down, only then noticing the body itself had changed. The burns looked as if they were nearly healed, her skin had more colour to it and though it seemed impossible to him her missing body parts seemed to be re-growing.

Bruce moved away quickly, "its Remarkable," gathering himself he moved to the phone on the wall and dialled Fury's number.

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Once I realised I was dreaming my eyes sprung open, taking in my surroundings, a white linen bed, no windows, metal walls, a simple bedside cabinet with a small vase of flowers on it. This place could have been anywhere but I almost feel at home here. The low hum of engines, the almost clinical smell and the quiet all screamed Hellicarrier.

I pulled myself up into the seating position and looked around to get better surroundings; it was my own room whenever I was on missions for S.H.I.E.L.D. At the end of my bed was a chair covered in my spare clothes I had with me on my last mission. I looked down to see what I was wearing, simple S.H.I.E.L.D standard clothing, I sighed.

I noticed my skin, not my usual colouring and it was puckered and red in places, frustrated I ran my hand through my hair and almost screamed. It felt wrong and without thinking I rushed to look in the mirror and ungracefully fell out of the bed. I looked closely at my legs while sitting on the floor, one looked paler than the other, I could have cried, I lost a leg!

It was at that moment of patheticness that the one and only Nick Fury walked in, great.

"'Bout time you got your ass up," he grinned, "although I expected you to be at least standing."

"Ha bloody ha," I croaked realising I probably have drunk anything in a while. I reached my hands towards him and he got the message. Fury pulled me up and sat me back on my bed then proceeded to pour me some water, "thanks."

As I gulped back the water I got feeling back into my leg and began moving each muscle and bone in turn till it was back to normal, Fury watching me the whole time, "so, what happened to me?"

"From what we gather from the information we found, it was shortly after your last mission after you handed us the relevant information to complete the task. No one was expecting you back so no-one realised you was missing," He paused looking apologetic at me, "and from the reports from the base you were at you put up a hell of a fight, took out a third of the base itself and destroyed decades of research."

It was a rare sight but Director Nick Fury was grinning at me, I couldn't help to grin back, "so I did good? How long was I out?"

That made Nick lose his smile, "six years, and you missed so much. If you're ok to walk you can read up on it in records before the meeting tomorrow at 11am."

"I can walk, but I need to get changed," Nick understood and headed for the door, "wait! A meeting already? Where?"

"New York, Stark Tower," he called back, "and part of the meeting's about you."

A Stark Tower? Not Tony Stark! What does he have to do with anything?! I looked at my clock seeing how long I had till the meeting, nearly midnight, plenty of time to read six years worth of reports. I moved putting on my clothes and headed for records and hoped everything I need answered would be answered there.


	4. Chapter 4

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I slunk down the corridor head to toe in black, my standard clothing colour, I left my jacket in my room which meant my pale arms were striking against the tank top and leather biker clothing. My black hair hung down my back, slowly re-growing to its normal length.

It was quiet and I didn't wish to be disturbed so as I left my box of a room I put my secondary ability to work. Healing was an ability I was born with while others presented themselves throughout my life, the second of which was an ability to turn myself and thing connected to me completely invisible. This had come to me at the time of my coming of age and had frighten me as I could not control it, but after surviving as long as I have I managed to, recently after meeting with a professor on the matter it was discovered I was a mutant.

Silent I crept down the hallways in my invisible form, careful to dodge the late shift agents, as I came to the end of the corridor I had two options, right leading me to records and left to the bridge. A mix of curiosity and procrastination lead me away from my goal and to the bridge where unfortunately not much had changed.

I listened in on some conversations regarding a group called the Avengers and their latest mission, in which I stifled a snigger cause I realised that was the group Fury had continuously tried to set up to no avail and they were the ones who found me. It was when the conversation took a meaningless turn into their personal lives I decided to move on. I moved past sonar and radar monitors; GPS mapping charts; a guy playing Galaga and information an enemy spy would have a field day coming across; and I took it all in but the one thing I wanted to see, the thing that never changed was the view.

Moving to the giant windows showing the way I stood barely moving staring into the endless night, clouds forming a billowing blanket below the hull and nothing but stars and darkness above, I loved it all. It wasn't until someone cleared their throat behind me that I snapped back into the present

"You know you still show up on the thermal image scanners," smirked Agent Hill.

"yeah, but most people still don't realise," I sighed turning to face her and becoming visible.

"Fury didn't mention you'd be coming to the Bridge, just records," the way she spoke it was almost like she didn't want me on the Hellicarrier let alone the Bridge, "haven't you got something better to be doing?"

I wasn't going to get defensive towards her but I did have somewhere to be, I gave the agent a sweetly sick grin, "unfortunately I do, but don't worry Miss Hill I'll be back."

I practically skipped away as the agent was left standing at the front of the bridge looking unsure of what to do next and I was still grinning as I sat down and begun the boring task of reading up on whatever it was I missed.

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At 8:30 I was just starting on the Avengers report, having gotten through the New Mexico report which to my amusement featured Asgardians I had not seen since the dark ages; and now it seemed they were involved in the Avengers.

"Still reading up? You've gotten slow," Fury stood by the door way, both Clint and Natasha standing beside him, "you ready to go Stark Tower?"

"its bit early isn't it," I frowned staring at the clock on the wall.

"I got some business to attend to in Manhattan, I'm dropping you off and then joining later," Fury explained, "by the way make sure you take your stuff with you, we got you an apartment in New York."

"That was quick, trying to get rid of me?" I smiled as I snuck past him and made my way to my room.

"Flight deck, 10minutes," was Fury's response.

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The journey was a quiet one, the last time I had spoken to both Clint and Natasha they worked for different sides and I had helped train them both. On top of that there were some pages missing in records that seemed to be getting to me.

"There it is," sighed Natasha breaking the silence, "the Stark Tower."

I unclipped my seat belt and stood up behind the cockpit. Coming up fast seemed to be a building that looked out of place. Everything thing about it screamed attention seeking and it incorporated so many different styles it gave me a headache, "that big ugly building?"

"yep," replied Clint, "we're coming into land."

As it turned out I was the only one being dropped off at this time, apparently whatever it was in Manhattan was no concern of mine. I was left alone in a room that sat atop the tower looking out over the city, which appeared to be a living room plus a bar area and I wondered if Nicks order to 'make myself at home' should be taken literally.

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	5. Chapter 5

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With Tony:

_"Sir may I suggest that you get up now," _Jarivs had not given up in his attempts to get Tony up and considering he had been alerting him for well over an hour,_ "the meeting is at 11am and its gone 10.30."_

"Once again, I KNOW!" Tony argued into his pillow, "I'll arrive fashionably late."

"You may wish to get there quite quickly actually," Jarvis explained, "a guest has been there for a while and is causing trouble with my wiring."

At that exact moment Jarvis' voice cut out and was replaced with the opening beat to Highway to Hell.

Tony head shot up, he was tired and hung-over and while he was a fan of the song it was not the time to have it blare out at full volume.

"Enough Jarvis! Jarvis! Jarvis?" Tony processed what Jarvis had been saying to him moments before and pulled himself up to his wardrobe, if he was to see who was causing him to leave his room; he was at least going to look smart about it. While he was waiting for the elevator to the floor the song was finishing and another, even louder, song was staring. Once the doors opened he was tempted to head back to his room.

"Bruce, Steven," he greeted the two Avengers with a false smile and stepped inbetween them.

"Bit early for this type of music, isn't Stark?" Steve was barely audible over the music but Tony still heard him. He turned to Steve raised his hand to his ear and gestured that he couldn't hear him. The elevator opened straight onto the floor and a sight that made each of the men stop dead in their tracks.

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I watched as each of them stepped out of the elevator; the soldier, the tin man and the monster. They all stopped upon entering the room, mouths gawping at my handy work. Stark's penthouse living room has been transformed by yours truly into my own private work space.

Upon arrival at Stark Tower I realised I hadn't had a chance to look through the duffel bag I had left in Fury's possession since my last mission. I had sat down on the floor ignoring the overly comfy sofa's and emptied the bags entire contents onto the floor. Inside were 3 identical cellphone's; 2 laptops; several pieces of GPS tracking equipment; a container full of ear pieces, timers, bugs and cameras; goggles that had various types of vision, all the cables to go with the electronics and three inner bags. In one of those bags was clothing with toiletries, another was a basic wilderness survival bag (camp stove, foil blanket, etc) and the last was my favourite; a selection of knives, smoke bombs and grenades.

The electronics I spent no time recharging, using the length of his bar and his home's computer, called JARVIS of all things, to make sure each piece could not be traced or bugged, while I used the coffee table and the sofa area to lay out each weapon to be checked and cleaned. In the middle of the room lay the duffel bag and rest of equipment ready to be checked and repacked. I took several of the cushions lining the couch over floor so I had something to sit on when I packed and started repacking the bag.

However it wasn't long before I got bored and decided to investigate the room. My first port of call was the bar, when I realised I haven't had a proper drink in 6 years I felt my mouth go dry and I searched for something to quench it. After almost downing a bottle of Jack I pick up vodka bottle and headed to the book shelf. Now many have called me an alcoholic in the past but I like to think of myself a seasoned drinker, with my constant healing ability I sober up quicker than normal people therefore I very rarely feel the effects.

When I got to the bookshelf I stared at it and all the nondescript books lining the shelves. I sighed almost giving up until I spotted several books that looked different from the rest. Pulling one out I realised it was a photo album and walked it over to the sofas. I placed it down along with my vodka and went back for the rest. I had planned to look at them but first I went back to check on my electronics. The phones were charged so I sent out my usual group text to my clients informing them that I was back, noticing that I had way to many unread texts, I deleted them without looking, then went to the home computer JARVIS to see if there was any sort of music to play since it was so quite.

When it informed me that there was but it suggested that I ask Mr Stark beforehand I decided that messing with its wiring and finding the music myself was the best answer. Turning up the volume my head nodded; stepping away I made my way back to the photo albums, flicking through the dated images. I paused when I recognised something; an old group picture, probably from the 70's, with several familiar faces smiling out, mine included. Howard Stark holding his son in his arms, a young Nick Fury with both eyes intact, a woman I vaguely remembered called Peg, a few old veterans of WWII, The Professor and Eric, a few other unknown "mutants", a vile abusive man by the name of Brian Banner and a handful of other military personal. With a smile I pulled it out of the album and tucked it inside my pocket, only then hearing the faint sound of an elevator approaching the floor. Time to disappear.

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End file.
